Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1990-1994
  • 1975-1979  (3)
  • Spektrometrie, ICP  (2)
  • Electroultrafiltration  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Determination of categories of soil nitrogen by electro-ultrafiltration (EUF) (1979)
    Springer
    Plant and soil 53 (1979), S. 445-453 
    Details
    ISSN: 1573-5036
    Keywords: Alluvial soils ; Ammonium ; Amino acids ; Chernozem ; Clay minerals ; Electroultrafiltration ; EUF Nitrate ; Nmin ; N release ; N reserves
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The determination of N fractions in the soil by means of electro-ultrafiltration (EUF) is described. The results can be summarized as follows: 1) For aqueous soils suspension the direction of NH4 + and NO3 − migration in an electric field is determined by electrical charge and water flow. Therefore the filtrates obtained at both the cathode and anode can be mixed for subsequent analysis for NH4−N and NO3−N. In order to avoid N losses the volatile NH3 is recovered in 1N HCl solution. 2) Considerable amounts of NH4−N and NO3−N as well as low-molecular organic N compounds can be determined by EUF in soil samples taken from June to September. The readily available N is extracted by EUF at 20°C and 200 V, while determinations at 80°C and 400 V also give information on N release from reserves. 3) It was demonstrated with soils from long term N and K fertilizer experiments that the EUF−NO3 contents reflect the N accumulation in the soil due to N fertilization or plant residues. In clayrich soils the EUF−NH4 contents give information on the release of fixed NH4. Moreover EUF−NH4 also gives information on N from readily mineralizable organic compounds. The EUF procedure gives improved insight into the N dynamics of a site and this should serve as a basis for N-fertilizer recommendations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02140716
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Einsatz der ICP-Emissionsspektrometrie zur simultanen Multielementanalyse (1977)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 284 (1977), S. 177-187 
    Details
    ISSN: 1618-2650
    Keywords: Analyse von Wasser, Stahl ; Spektrometrie, ICP ; Optimierung, Multielementanalyse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die induktiv gekoppelte Plasma-Emissionsspektrometrie wird gegenwärtig zu einem wichtigen analytischen Werkzeug in Routinelaboratorien. Der Einsatz der ICP-Emissionsspektrometrie wird an den analytischen Anforderungen gemessen. Die simultane Bestimmung von Al, B, Cr, Cu und Mn in Abwasser oder Lösungen aus Stahlproben wird als Beispiel herangezogen. Die reellen Bestimmungsgrenzen für zahlreiche Elemente aus Stahl, die von dem eingesetzten Apparat und den Arbeitsbedingungen abhängen, werden mitgeteilt. Die wichtigsten Parameter wie Abstimmung zwischen Generator, Impedanzwandler und Spule, die Art des Zerstäubers, die Proben-Aerosolgasmenge und die Beobachtungshöhe im Plasma werden diskutiert.
    Notes: Abstract The inductively coupled plasma emission spectrometry is becoming a very important analytical tool in routine laboratories today. The application of ICP emission spectrometry in comparison to the analytical needs is described. The simultaneous determination of Al, B, Cr, Cu and Mn in waste water or steel solution is taken for example. The real limits of determination for several elements from steel samples depending on the applied ICP/spectrometer device and the working conditions are given. The most important parameters like tuning between generator, matchbox and coil, the kind of nebulizer, the sample flow gas rate and the observation height in the plasma are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00592226
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Comparison of two pneumatic nebulizers for use in ICP emission spectroscopy (1977)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 287 (1977), S. 10-14 
    Details
    ISSN: 1618-2650
    Keywords: Spektrometrie, ICP ; Multielementanalyse ; Aerosolherstellung, pneumatische Zerstäuber
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Summary The connexions between aerosol gas flow and optimal observation height were experimentally illustrated by comparing two pneumatic nebulizers. If we succeed in getting a higher sample flow with lower aerosol gas velocity, the remaining time of the aerosol in the plasma flame will be considerably prolonged. This results in a maximum emission of all elements studied up to now at the lowest possible observation height of the plasma flame. Thus an essential supposition for simultaneous multielement analysis is fulfilled: A height correction between single element measurements does not cause an improvement, the plasma flame can be firmly installed in the optical axis. The detection limits of all studied elements are considerably improved by the prolonged remaining time. The reproducibility of the measurements is ≤ 1% in the concentration range up to 10 ng/ml.
    Notes: Zusammenfassung Durch den Vergleich zweier pneumatischer Zerstäuber wurden die Zusammenhänge zwischen Aerosolgasrate und optimaler Beobachtungshöhe experimentell verdeutlicht. Wenn es gelingt, mit geringer Aerosolgasgeschwindigkeit einen höheren Lösungsdurchsatz zu bewirken, dann wird auch die Verweilzeit des Aerosols in der Plasmaflamme erheblich verlängert. Dadurch wird bewirkt, daß alle bisher untersuchten Elemente in der geringst möglichen Beobachtungshöhe der Plasmaflamme eine maximale Emission zeigen. Somit ist für die simultane Multielementanalyse eine wesentliche Voraussetzung erfüllt: Eine Höhenkorrektur zwischen Einzelelement-Messungen führt zu keiner Verbesserung, die Plasmaflamme kann in der optischen Achse fest installiert werden. Die Bestimmungsgrenzen aller untersuchten Elemente werden durch die verlängerte Verweilzeit erheblich verbessert. Die Reproduzierbarkeit der Messungen im Konzentrationsbereich bis zu 10 ng/ml beträgt ≤ 1%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00539520
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...